Thomas e



(No Model.)

T. E. DROHAN.

ELECTRIC ARG LAMP.

No. 594,682. Patented Nov. 30,1897.

UNITED STATES PATENT FFICE.

THOMAS E. DROHAN, OF CHICAGO, ILLINOIS, ASSIGNOR TO THE SIEMENS d: HALSKE ELECTRIC COMPANY OF AMERICA, OF SAME PLACE.

ELECTRIC-ARG LAM P.

SPECIFICATION frming part of Letters Patent No. 594,682, dated November 30, 1897.

Application filed July 9, 1897. Serial No. 643,943. (No model.)

To all whom L'25 may concern:

Be it known that I, THOMAS E. DROHAN, a citizen of the United States, residing at Chi cago, in the county of Cook and State of Illinois, have invented new and useful Improvements in Electric-Arc Lamps, of which the following is a specfication.

My invention relates to an electric are lamp; and its object is to provide means for preventing the total release of the carbon when the latter is nearly consumed.

My invention is especially applicable to an arclamp wherein one of the carbons loosely fits in a bodilymovable tubular portion,

r5 clutch mechanism carried by said tubular portion being adapted to grip said carbon or to release the same to effect regulation of the length of aro. A fanlt in lamps of this character has been that the clutch mechanism was liable to totally release the carbon, causing it to fall and short-circuit or otherwise damage the lamp. It is to obviate this difficulty without interfering with the sensitiveness of the mechanism which regulates the feeding 2 5 of the carbon that myinvention is designed. My invention will be readily understood by reference to the accompanying drawing, which is a diagrammatic illustration of an aro-lamp embodying my invention.

In the drawing, CL represents a solenoid electrically connected in series With the aro, the solenoid having a hollow iron core Z), provided with a tubular extension l), through which the upper carbon d is fed. A slot b is 3 5 provided near the lower end of the tubular extension b, through which slot the clutchlever o engages With the carbon d, being pivoted at o to said tubular extension. The outer end of the lover c is enlarged to form 0 a weight c An ad j ustable stop e is provided upon a portion f of the frame of the lamp, this stop lying in the path of the enlarged end c of the clutch-lever.

During the burning of the lamp when the 5 ends of the carbons become consumed and the resistance of the are increased the pull of the solenoid upon its core b is lessened, thus allowing the core and the tubular extension thereof to descend by their own weight,

whereupon the enlarged end c" of the clutchlever c is engaged by the stop e, thus releasing the carbon (Z and permitting the latter to fall. Upon the proper length of are being established the solenoid CL is actuated to lift its core and the tubular extension thereof, the end c of the clutch-lever c being withdrawn from engagement with the stop e and the lever caused again to clutch the carbon, checking its further descent.

In order to prevent the carbon when nearly consumed from falling entirely out of the tubular part I) and damaging the lamp, I have devised a simple catch mechanism to prevent the release of the carbon after its upper end has passed a given point in its downward path. This consists of a weighted trigger g, pivoted at g to a portion of the frame of the machine, the rounded end g of the trgger riding upon the surface of the carbon d through a slot l) provided in the tubular part b. This engagement, however, is light and in no way impedes the proper action of the clutching mechanism.

It will be seen upon an inspection of the drawing that when the upper end d of the carbon passes the end g of the trigger the latter will be no longer supported and will fall by its own weight into the slot Z) being checked, however, in its further descent by a stop h, provided upon the frame of the lamp for this purpose. The tubular extension, being now engaged by the end g of the trigger, is prevented from descending sufficiently to allow the carbon cl to be released by the engagement of the clutch-lever with the stop e. The aro will now simply burn itself out and cause no damage to the lamp.

It will be seen that modifications may be made in my invention over the form shown in the drawing, and I do not, therefore, desire to be limited to this precise construction; but,

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is

1. In an electric-aro lamp, the combination with a longitudinally-movable tubular por tion through which the carbon may freely pass, of a clutchlever pivoted to said tubular portion and normally engaging the oar bon, a stop in the path of said clutch-lever adapted to engage therewith and cause the same to release the carbon, means for preventing the engagement of the eluteh-lever with said stop to prevent the total release of said carbon from the tubular portion after it has passed a given point therein, and electromagnetic means for eausing the movement of said tubular portion to effect thereby the regulation of the lamp, substantially as described.

2. In an electric-are lamp, the combination with a solenoid, of a hollow iron core there for having a tubular extension through which the earbon may freely pass, a cluteh-lever pivoted to said tubular extension and normally engaging the carbon, a stop in the path of said clutch-lever adapted to engage therewith and cause the same to release the carbon, and means for preventing the total release of the carbon after the latter has passed a given point in said tubular portion, sub stantially as described.

In an electrieare lam p, the combination with a tubular part through which the carbon is adapted to be fed, of a trigger adapted to rest upon the carbon as it is fed through said passage and to engage with said tubular part after the carbon has passed the trigger, substantially as and for the purpose specified.

4. In an electric-are lamp, the combination with a movable tubular part through which the earbon is adapted to be fed, of eluteh mechanism carried by said tubular part, and normally engaging the earbon, a stop in the path of said clutch mechanism adapted to engage therewith to cause the same to release the carbon, means for preventing the release of the earbon after it has passed a given point in said tubular part, and electrieall5 operated means for causing the movement of said tubular part, to effect thereby the regulation of the lamp, substantially as described.

5. In an electric-are lamp, the combination with a movable tubular portion through which the carbon is adapted to be fed, of clutch mechanism carried upon said tubular portion and normally engaging the carbon, a stop in the path of said cluteh meehanism adapted to engage therewith to cause the release of the carbon, a stop adapted to rest upon the earbon as it is fed through said tubular por tion and to engage with said tubular portion after the carbon has passed the stop, and eleetrieally-operated means for causing the movement of said tubular portion, substau tially as and for the purpose described.

(5. ln an electric-are lamp, the combination with a solenoid having a hollow iron core, of a cluteh-lever carried thereby and normally engaging the carbon, a stop in the path of said clutch-lever adapted to engage therewith and cause the release of the earbon, and a trigger resting upon the carbon as it is fed through said core and to engage with the core after the carbon has passed the trigger, sub stantially as and for the purpose described.

In testimouy whereof l alfix my signature in the presence of two witncsscs.

THOMAS la. Hlt0lljxN.

W itnesses J. Il. Emus, KONRAD LW. 

